1. Field of the Invention
The present invention relates to a micro-traction drive that can be accommodated in a small apparatus, is less likely to be damaged, and can provide a large reduction ratio and a high torque.
2. Description of the Related Art
A small apparatus that has a rotational driving source, such as a motor, and rotationally drives a working portion at the tip, such as a small drilling apparatus for soil survey or a turbine-rotor center core replica sampling apparatus, needs to have a micro-traction drive provided therein, which transmits a reduced rotation speed.
Accordingly, various configurations of micro-traction drives have been proposed (for example, see PTLS 1 and 2).
Because micro-traction drives are adapted from roller bearings, they are known to have features of low manufacturing cost, low noise, and low vibration, compared with traction drives using gears.